More than 500 measurable earthquakes have been reported in central Arkansas since September 20, ranging in magnitude from a barely noticeable 1.8 to a very noticeable 4.0 (recorded on October 11), according to the U.S. Geological Survey.

Geologists can't say whether they'll stop anytime soon.

Steve Wilson is looking forward to the quakes going away, he said.

"In the beginning, it was fun, it was neat, it was a cool thing to experience. But now we're wanting it to go away," said Wilson, assistant superintendent at Woolly Hallow State Park. "We've had all the fun we want."

Although drilling for natural gas has been ruled out as a cause for the quakes, experts want to continue looking at salt water disposal wells, said Scott Ausbrooks, geohazards supervisor for the Geological Survey. Disposal wells occur when drilling waster is injected back into the earth after drilling.

Earlier this month, the Arkansas Oil and Gas commission issued an emergency moratorium on permits for new disposal wells. The commission will ask for a six-month extension for the moratorium at a January regulatory meeting.

The state also will soon become one of a few to require companies to disclose the chemicals used in fracking fluid, the water-and-chemical solution used in high-pressure drilling operations, said Shane Khoury, deputy director and general counsel for the Arkansas Oil and Gas Commission.

"I think everyone recognizes that there is an increased number of seismic events occurring in and around this area. If you look at the maps, at least circumstantially, there appears to be evidence that they may be related to disposal operations," said Khoury. "But we also know that this is an area that is historically active."

Although drilling for natural gas has been ruled out as a cause for the quakes, experts want to continue looking at salt water disposal wells, said Scott Ausbrooks, geohazards supervisor for the Geological Survey. Disposal wells occur when drilling waster is injected back into the earth after drilling.

The state also will soon become one of a few to require companies to disclose the chemicals used in fracking fluid, the water-and-chemical solution used in high-pressure drilling operations, said Shane Khoury, deputy director and general counsel for the Arkansas Oil and Gas Commission.

"I think everyone recognizes that there is an increased number of seismic events occurring in and around this area. If you look at the maps, at least circumstantially, there appears to be evidence that they may be related to disposal operations," said Khoury. "But we also know that this is an area that is historically active."

Well, that sounds like a really good idea! Lets inject water and chemicals deep into the earth where there's a known seismic fault that has caused the worst earthquakes in recorded history in the US!

Although drilling for natural gas has been ruled out as a cause for the quakes, experts want to continue looking at salt water disposal wells, said Scott Ausbrooks, geohazards supervisor for the Geological Survey. Disposal wells occur when drilling waster is injected back into the earth after drilling.

The state also will soon become one of a few to require companies to disclose the chemicals used in fracking fluid, the water-and-chemical solution used in high-pressure drilling operations, said Shane Khoury, deputy director and general counsel for the Arkansas Oil and Gas Commission."I think everyone recognizes that there is an increased number of seismic events occurring in and around this area. If you look at the maps, at least circumstantially, there appears to be evidence that they may be related to disposal operations," said Khoury. "But we also know that this is an area that is historically active."

Well, that sounds like a really good idea! Lets inject water and chemicals deep into the earth where there's a known seismic fault that has caused the worst earthquakes in recorded history in the US!

I could not agree more. I am of the opinion that while everyone is waiting for the big one in California, the big one is going to hit in the New Madrid zone. Asa they are not ready at all, it will be real bad!

I agree with what both of you said regarding the earthquakes in north central Arkansas. Granted it IS a seismically active area, but it seems to become more so since they started drilling for gas.

I am also waiting on the "Big " one from the New Madrid fault, especially since it has almost 200 years since the last time. When that happens, it will be BAD. I mean think about it. Between 55% - 60% of the population of the U.S. lives east of the Mississippi River and the first quake was felt in Boston, MA. Here is a page from the U.S.G.S website with a map of the of the estimated shaking intensity http://earthquake.usgs.gov/earthquakes/states/events/1811-1812_iso.php.

The other "big" one I am waiting on is the Cascadia Subduction Zone off the West Coast.

....Well, that sounds like a really good idea! Lets inject water and chemicals deep into the earth where there's a known seismic fault that has caused the worst earthquakes in recorded history in the US!

Ditto! I wonder what kind of pressures they are using to inject the waste water? I'm betting it is a wee bit more then just filling the pipe until it runs over the top. Wonder if they are storing NG underground there as well.

They could be if there is salt domes to cap the storage area.Upstate NY has lot of swarms quakes also and no one been able to come up with an answer to that one. Here in Alaska we are due for an 7.) or greater been 7 years since the last good one 7.4.

Alaska had quite a large earthquake back in the 60's did they not? Seem to remember that it was very large and was accompanied by a fairly large tsunami. I can remember the news at the time and saw a TV program about it sometime back. If I remember right it was in the area of the Gulf. I remember seeing a street that had a big crack and uplift in the middle of it. Ate some cars if my memory serves right.

Good Friday Quake 9.4 mag....... raise some area as much as 40 feet Wiped Valdez off the map..... Tore Anchorage apart. Street you mention and Seward was hit bad to by wave.

Tsuamini killed people as far away as Crescent City, Cal.

The good thing it was not in the dead of winter when those towns hit 20 below. At Valdez they found railcars washed an mile inland. There the complete underwater entrance to the Harbor collaspse dropping 300 feet.

I believe that small tremors release pressure over time, so that the big one is postponed. While looking at maps and stuff the other day, I noticed that there's a connection between New Madrid seismic zone and the Wabash seismic zone. A straight line would connect them. So, you're free to draw your own conclusions. I think it's interesting to consider.

I believe that small tremors release pressure over time, so that the big one is postponed. While looking at maps and stuff the other day, I noticed that there's a connection between New Madrid seismic zone and the Wabash seismic zone. A straight line would connect them. So, you're free to draw your own conclusions. I think it's interesting to consider.

My town is just above the second "L" on the map and we have been shook by the New Madrid in the past. Last one was a 5.2 quake in April 2008. It shook the town in the early morning at around 3 or 4 am and then again at around 9 am. Before that I remember something in the late 60's when everything in the house vibrated for about 30 seconds and that's when the New Madrid became more well known in the news.

There has been some evidence suggesting that the New Madrid zone is settling down. However, one of the things that I find particularly interesting about intraplate earthquakes is that it is thought that the seismic activity can migrate. If you are interested, 'Continental Intraplate Earthquakes: Science, Hazard and Policy Issues' (Geological Society of America) might be worth checking out.

Logged

There is ALWAYS more toothpaste in the tube. Think about it. (Bill Bryson)

I tell ya as a midwesterner we are used to tornadoes, hail, lighting, wind, rain, river flooding, blizzards, you name we have it. However in my life I've only felt two earthquakes and they were minor and still scared the crap out of me. I hope and pray we never see the big one here.

We've been getting a lot of rumblies lately centering around Mt. St. Helens, and in the news this morning, they are talking about Mt. Baker gettin' busy. You can see Mt. Rainier from my house (the pic in my sticker is actually from Tacoma) which is the big one around here.